disable adc channels while reconfiguring

Author: Owen L - SFE

cores/arduino/ard_sup/analog/ap3_analog.cpp

@@ -119,14 +119,15 @@ static const uint8_t outcfg_tbl[32][4] =
         {OUTC(1, 7, 1), OUTC(0, 6, 0), OUTC(1, 7, 0), OUTC(1, 3, 1)}, // CTX31: B7OUT2, A6OUT,  B7OUT,  B3OUT2
 };
 
-uint16_t _analogBits = 10;    //10-bit by default
-uint8_t _analogWriteBits = 8; // 8-bit by default for writes
-uint8_t _servoWriteBits = 8;  // 8-bit by default for writes
+uint16_t _analogBits = 10;               //10-bit by default
+uint8_t _analogWriteBits = 8;            // 8-bit by default for writes
+uint8_t _servoWriteBits = 8;             // 8-bit by default for writes
 static bool ap3_adc_initialized = false; // flag to show if the ADC has been initialized
 
 uint16_t analogRead(uint8_t pinNumber)
 {
-    if(!ap3_adc_initialized){
+    if (!ap3_adc_initialized)
+    {
         ap3_adc_setup();
         ap3_adc_initialized = true;
     }
@@ -297,13 +298,6 @@ ap3_err_t ap3_adc_setup()
         return AP3_ERR;
     }
 
-    // Enable the ADC.
-    if (AM_HAL_STATUS_SUCCESS != am_hal_adc_enable(g_ADCHandle))
-    {
-        //Serial.println("Error - enabling ADC failed.\n");
-        return AP3_ERR;
-    }
-
     return AP3_OK;
 }
 
@@ -350,6 +344,11 @@ ap3_err_t ap3_change_channel(uint8_t padNumber)
     ADCSlotConfig.eMeasToAvg = AM_HAL_ADC_SLOT_AVG_1;
     ADCSlotConfig.ePrecisionMode = AM_HAL_ADC_SLOT_14BIT;
 
+    if (AM_HAL_STATUS_SUCCESS != am_hal_adc_disable(g_ADCHandle))
+    {
+        return AP3_ERR;
+    }
+
     //Look up adc channel based on pad number
     uint8_t indi;
     for (indi = 0; indi < AP3_ANALOG_CHANNELS; indi++)
@@ -375,6 +374,11 @@ ap3_err_t ap3_change_channel(uint8_t padNumber)
         return AP3_ERR;
     }
 
+    if (AM_HAL_STATUS_SUCCESS != am_hal_adc_enable(g_ADCHandle))
+    {
+        return AP3_ERR;
+    }
+
     return AP3_OK;
 }
 
@@ -667,12 +671,12 @@ ap3_err_t servoWriteResolution(uint8_t res)
 
 uint8_t getServoResolution()
 {
-    return(_servoWriteBits);
+    return (_servoWriteBits);
 }
 
 ap3_err_t servoWrite(uint8_t pin, uint32_t val)
 {
-    return(servoWrite(pin, val, 544, 2400)); //Call servoWrite with Arduino default min/max microseconds. See: https://www.arduino.cc/en/Reference/ServoAttach
+    return (servoWrite(pin, val, 544, 2400)); //Call servoWrite with Arduino default min/max microseconds. See: https://www.arduino.cc/en/Reference/ServoAttach
 }
 
 ap3_err_t servoWrite(uint8_t pin, uint32_t val, uint16_t minMicros, uint16_t maxMicros)
@@ -684,9 +688,9 @@ ap3_err_t servoWrite(uint8_t pin, uint32_t val, uint16_t minMicros, uint16_t max
     uint32_t fw = 60000;                      // 20 ms wide frame
 
     //Convert microSeconds to PWM counts.
-    uint32_t min = minMicros * 3; 
+    uint32_t min = minMicros * 3;
     uint32_t max = maxMicros * 3;
-    
+
     uint32_t th = (uint32_t)(((max - min) * val) / fsv) + min;
 
     return ap3_pwm_output(pin, th, fw, clk);